Stereoscopic PIV measurements of flow in the nasal cavity with high flow therapy

• Published in: Experiments in fluids Vol. 50; no. 4; pp. 1005 - 1017
• Main Authors: Spence, C. J. T., Buchmann, N. A., Jermy, M. C., Moore, S. M.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01-04-2011; Springer
• Subjects: Airflow; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Biological and medical sciences; Biomedical materials; Emergency and intensive respiratory care; Engineering; Engineering Fluid Dynamics; Engineering Thermodynamics; Exact sciences and technology; Expiration; Fluid dynamics; Fluid- and Aerodynamics; Fundamental areas of phenomenology (including applications); Heat and Mass Transfer; Holes; Instrumentation for fluid dynamics; Intensive care medicine; Medical materials; Medical sciences; Physics; Research Article; Surgical implants; Therapy; Tubes; Particle Image Velocimetry Measurement; Stereoscopic Particle Image Velocimetry; Nasal Valve; Nasal Cavity; Particle Image Velocimetry; Human; Oxygenotherapy; Air flow; Cannula; Stereoscopy; Nose; Speed measurement; Particle image velocimetry; Measurement method; Experimental study; Respiration
• ISSN: 0723-4864; 1432-1114
• DOI: 10.1007/s00348-010-0984-z

Knowledge of the airflow characteristics within the nasal cavity with nasal high flow (NHF) therapy and during unassisted breathing is essential to understand the treatment’s efficacy. The distribution and velocity of the airflow in the nasal cavity with and without NHF cannula flow has been investigated using stereoscopic particle image velocimetry at steady peak expiration and inspiration. In vivo breathing flows were measured and dimensionally scaled to reproduce physiological conditions in vitro. A scaled model of the complete nasal cavity was constructed in transparent silicone and airflow simulated with an aqueous glycerine solution. NHF modifies nasal cavity flow patterns significantly, altering the proportion of inspiration and expiration through each passageway and producing jets with in vivo velocities up to 17.0 ms
−1
for 30 l/min cannula flow. Velocity magnitudes differed appreciably between the left and right sides of the nasal cavity. The importance of using a three-component measurement technique when investigating nasal flows has been highlighted.